Historically, hydrofinishing technologies have used both base and noble metal catalysts on an amorphous support. With noble metal catalysts, excellent color and oxidation stability can be achieved at lower pressures and temperatures with smaller reactor volumes than those required when using base metal catalysts. At higher processing temperatures, color quality is sacrificed to achieve sufficient oxidation stability. With noble metal catalysts, it is possible to get superior color stability (water-white), excellent oxidation stability, and almost complete removal of aromatics. However, noble metal catalysts are poisoned by sulfur and are only used to hydrofinish feeds containing very low levels of sulfur.
U.S. Patent Application Publication 2006/0070917 describes a process for hydrogenating lube oil boiling range feedstreams using a catalyst comprising at least one Group VIII noble metal selected from Pt, Pd, and mixtures thereof on a support material having an average pore diameter of about 15 to less than about 40 Å. The support material for the at least one Group VIII noble metal can include MCM-41 mesoporous support materials, such as MCM-41 support materials composed of SiO2 and Al2O3.
There is still a need in the art for improved catalysts and/or processes for hydrofinishing and aromatic saturation of hydrocarbon feeds.